Manohar and Deepak 01 04 Our suggestion is to employ a single ended primary inductance converter SEPIC as a frontend device to provide unipolar current to a permanent magnet brushless dc BLDC motor In series with each phase a switch is added Their drive specs are a little easier to understand because all of the switches gate drives have ground references Additionally low voltage applications benefit from being able to increase the available input voltage to better control current With the SEPIC converter sourced by an ac source it is preferable to use the discontinuous conduction mode At this operating mode the waveform of the line current is very close to that of the line voltage We demonstrate that power factor is improved with reduced low order harmonics without the use of voltage and current sensors The low cost and reduced number of components of the suggested topology makes it attractive for use in many types of variable speed drive applications Using MATLABSIMULIK the proposed topology is simulated and validated Copyright (c) Journal of Engineering Technology and Sciences. All rights reserved 2026